Tropical soda apple (Solanum viarum Dunal; TSA) is a prickly perennial weed species indigenous to South America. Introduced into Florida in 1988 it has since become one of the most serious invasive weeds in the southeastern United States (Mullahey, 1996). Tropical soda apple is designated a noxious weed under the Federal Noxious Weed Statutes. It proliferates rapidly by both sexual and asexual means. TSA is dispersed by cattle, birds, wild animals, and certain ranching and agricultural practices. In addition to being a highly competitive weed, TSA poses an additional threat as a reservoir for several economically important plant viruses (McGovern et al., 1994). TSA is currently managed by a combination of mowing and application of the chemical herbicide triclopyr (Remedy®) (Akanda et al., 1997), but alternative means of control are necessary and desirable.